util/Tokenizer: use std::runtime_error on syntax error

src/command/AllCommands.cxx

@@ -361,7 +361,7 @@ command_checked_lookup(Response &r, unsigned permission,
 
 CommandResult
 command_process(Client &client, unsigned num, char *line)
-{
+try {
 	Response r(client, num);
 	Error error;
 
@@ -371,13 +371,17 @@ command_process(Client &client, unsigned num, char *line)
 
 	Tokenizer tokenizer(line);
 
-	const char *const cmd_name = tokenizer.NextWord(error);
-	if (cmd_name == nullptr) {
-		if (tokenizer.IsEnd())
-			r.FormatError(ACK_ERROR_UNKNOWN, "No command given");
-		else
-			r.Error(ACK_ERROR_UNKNOWN, error.GetMessage());
-
+	const char *cmd_name;
+	try {
+		cmd_name = tokenizer.NextWord();
+		if (cmd_name == nullptr) {
+			r.Error(ACK_ERROR_UNKNOWN, "No command given");
+			/* this client does not speak the MPD
+			   protocol; kick the connection */
+			return CommandResult::FINISH;
+		}
+	} catch (const std::exception &e) {
+		r.Error(ACK_ERROR_UNKNOWN, e.what());
 		/* this client does not speak the MPD protocol; kick
 		   the connection */
 		return CommandResult::FINISH;
@@ -394,14 +398,9 @@ command_process(Client &client, unsigned num, char *line)
 			return CommandResult::ERROR;
 		}
 
-		char *a = tokenizer.NextParam(error);
-		if (a == nullptr) {
-			if (tokenizer.IsEnd())
-				break;
-
-			r.Error(ACK_ERROR_UNKNOWN, error.GetMessage());
-			return CommandResult::ERROR;
-		}
+		char *a = tokenizer.NextParam();
+		if (a == nullptr)
+			break;
 
 		argv[args.size++] = a;
 	}
@@ -412,14 +411,13 @@ command_process(Client &client, unsigned num, char *line)
 		command_checked_lookup(r, client.GetPermission(),
 				       cmd_name, args);
 
-	try {
-		CommandResult ret = cmd
-			? cmd->handler(client, args, r)
-			: CommandResult::ERROR;
+	CommandResult ret = cmd
+		? cmd->handler(client, args, r)
+		: CommandResult::ERROR;
 
-		return ret;
-	} catch (const std::exception &e) {
-		PrintError(r, e);
-		return CommandResult::ERROR;
-	}
+	return ret;
+} catch (const std::exception &e) {
+	Response r(client, num);
+	PrintError(r, e);
+	return CommandResult::ERROR;
 }

src/config/ConfigFile.cxx

@@ -41,26 +41,17 @@ static constexpr char CONF_COMMENT = '#';
 
 static constexpr Domain config_file_domain("config_file");
 
-static bool
-config_read_name_value(ConfigBlock &block, char *input, unsigned line,
-		       Error &error)
+static void
+config_read_name_value(ConfigBlock &block, char *input, unsigned line)
 {
 	Tokenizer tokenizer(input);
 
-	const char *name = tokenizer.NextWord(error);
-	if (name == nullptr) {
-		assert(!tokenizer.IsEnd());
-		return false;
-	}
+	const char *name = tokenizer.NextWord();
+	assert(name != nullptr);
 
-	const char *value = tokenizer.NextString(error);
-	if (value == nullptr) {
-		if (tokenizer.IsEnd())
-			throw std::runtime_error("Value missing");
-
-		assert(error.IsDefined());
-		return false;
-	}
+	const char *value = tokenizer.NextString();
+	if (value == nullptr)
+		throw std::runtime_error("Value missing");
 
 	if (!tokenizer.IsEnd() && tokenizer.CurrentChar() != CONF_COMMENT)
 		throw std::runtime_error("Unknown tokens after value");
@@ -71,7 +62,6 @@ config_read_name_value(ConfigBlock &block, char *input, unsigned line,
 					 name, bp->line);
 
 	block.AddBlockParam(name, value, line);
-	return true;
 }
 
 static ConfigBlock *
@@ -104,13 +94,8 @@ try {
 
 		/* parse name and value */
 
-		if (!config_read_name_value(*block, line,
-					    reader.GetLineNumber(),
-					    error)) {
-			assert(*line != 0);
-			error.FormatPrefix("line %u: ", reader.GetLineNumber());
-			return nullptr;
-		}
+		config_read_name_value(*block, line,
+				       reader.GetLineNumber());
 	}
 } catch (...) {
 	std::throw_with_nested(FormatRuntimeError("Error in line %u", reader.GetLineNumber()));
@@ -179,11 +164,10 @@ Append(config_param *&head, config_param *p)
 	*i = p;
 }
 
-static bool
+static void
 ReadConfigParam(ConfigData &config_data, BufferedReader &reader,
 		const char *name, ConfigOption o,
-		Tokenizer &tokenizer,
-		Error &error)
+		Tokenizer &tokenizer)
 {
 	const unsigned i = unsigned(o);
 	const ConfigTemplate &option = config_param_templates[i];
@@ -199,15 +183,10 @@ ReadConfigParam(ConfigData &config_data, BufferedReader &reader,
 
 	/* now parse the block or the value */
 
-	const char *value = tokenizer.NextString(error);
-	if (value == nullptr) {
-		if (tokenizer.IsEnd())
-			throw FormatRuntimeError("line %u: Value missing",
-						 reader.GetLineNumber());
-
-		error.FormatPrefix("line %u: ", reader.GetLineNumber());
-		return false;
-	}
+	const char *value = tokenizer.NextString();
+	if (value == nullptr)
+		throw FormatRuntimeError("line %u: Value missing",
+					 reader.GetLineNumber());
 
 	if (!tokenizer.IsEnd() && tokenizer.CurrentChar() != CONF_COMMENT)
 		throw FormatRuntimeError("line %u: Unknown tokens after value",
@@ -215,7 +194,6 @@ ReadConfigParam(ConfigData &config_data, BufferedReader &reader,
 
 	auto *param = new config_param(value, reader.GetLineNumber());
 	Append(head, param);
-	return true;
 }
 
 static bool
@@ -234,12 +212,8 @@ ReadConfigFile(ConfigData &config_data, BufferedReader &reader, Error &error)
 		   by either the value or '{' */
 
 		Tokenizer tokenizer(line);
-		const char *name = tokenizer.NextWord(error);
-		if (name == nullptr) {
-			assert(!tokenizer.IsEnd());
-			error.FormatPrefix("line %u: ", reader.GetLineNumber());
-			return false;
-		}
+		const char *name = tokenizer.NextWord();
+		assert(name != nullptr);
 
 		/* get the definition of that option, and check the
 		   "repeatable" flag */
@@ -247,9 +221,8 @@ ReadConfigFile(ConfigData &config_data, BufferedReader &reader, Error &error)
 		const ConfigOption o = ParseConfigOptionName(name);
 		ConfigBlockOption bo;
 		if (o != ConfigOption::MAX) {
-			if (!ReadConfigParam(config_data, reader, name, o,
-					     tokenizer, error))
-				return false;
+			ReadConfigParam(config_data, reader, name, o,
+					tokenizer);
 		} else if ((bo = ParseConfigBlockOptionName(name)) != ConfigBlockOption::MAX) {
 			if (!ReadConfigBlock(config_data, reader, name, bo,
 					     tokenizer, error))

src/util/Tokenizer.cxx

@@ -31,10 +31,8 @@
 #include "Tokenizer.hxx"
 #include "CharUtil.hxx"
 #include "StringUtil.hxx"
-#include "Error.hxx"
-#include "Domain.hxx"
 
-static constexpr Domain tokenizer_domain("tokenizer");
+#include <stdexcept>
 
 static inline bool
 valid_word_first_char(char ch)
@@ -49,7 +47,7 @@ valid_word_char(char ch)
 }
 
 char *
-Tokenizer::NextWord(Error &error)
+Tokenizer::NextWord()
 {
 	char *const word = input;
 
@@ -58,10 +56,8 @@ Tokenizer::NextWord(Error &error)
 
 	/* check the first character */
 
-	if (!valid_word_first_char(*input)) {
-		error.Set(tokenizer_domain, "Letter expected");
-		return nullptr;
-	}
+	if (!valid_word_first_char(*input))
+		throw std::runtime_error("Letter expected");
 
 	/* now iterate over the other characters until we find a
 	   whitespace or end-of-string */
@@ -75,10 +71,8 @@ Tokenizer::NextWord(Error &error)
 			break;
 		}
 
-		if (!valid_word_char(*input)) {
-			error.Set(tokenizer_domain, "Invalid word character");
-			return nullptr;
-		}
+		if (!valid_word_char(*input))
+			throw std::runtime_error("Invalid word character");
 	}
 
 	/* end of string: the string is already null-terminated
@@ -94,7 +88,7 @@ valid_unquoted_char(char ch)
 }
 
 char *
-Tokenizer::NextUnquoted(Error &error)
+Tokenizer::NextUnquoted()
 {
 	char *const word = input;
 
@@ -103,10 +97,8 @@ Tokenizer::NextUnquoted(Error &error)
 
 	/* check the first character */
 
-	if (!valid_unquoted_char(*input)) {
-		error.Set(tokenizer_domain, "Invalid unquoted character");
-		return nullptr;
-	}
+	if (!valid_unquoted_char(*input))
+		throw std::runtime_error("Invalid unquoted character");
 
 	/* now iterate over the other characters until we find a
 	   whitespace or end-of-string */
@@ -120,11 +112,8 @@ Tokenizer::NextUnquoted(Error &error)
 			break;
 		}
 
-		if (!valid_unquoted_char(*input)) {
-			error.Set(tokenizer_domain,
-				  "Invalid unquoted character");
-			return nullptr;
-		}
+		if (!valid_unquoted_char(*input))
+			throw std::runtime_error("Invalid unquoted character");
 	}
 
 	/* end of string: the string is already null-terminated
@@ -134,7 +123,7 @@ Tokenizer::NextUnquoted(Error &error)
 }
 
 char *
-Tokenizer::NextString(Error &error)
+Tokenizer::NextString()
 {
 	char *const word = input, *dest = input;
 
@@ -144,10 +133,8 @@ Tokenizer::NextString(Error &error)
 
 	/* check for the opening " */
 
-	if (*input != '"') {
-		error.Set(tokenizer_domain, "'\"' expected");
-		return nullptr;
-	}
+	if (*input != '"')
+		throw std::runtime_error("'\"' expected");
 
 	++input;
 
@@ -159,14 +146,8 @@ Tokenizer::NextString(Error &error)
 			   character */
 			++input;
 
-		if (*input == 0) {
-			/* return input-1 so the caller can see the
-			   difference between "end of line" and
-			   "error" */
-			--input;
-			error.Set(tokenizer_domain, "Missing closing '\"'");
-			return nullptr;
-		}
+		if (*input == 0)
+			throw std::runtime_error("Missing closing '\"'");
 
 		/* copy one character */
 		*dest++ = *input++;
@@ -176,11 +157,8 @@ Tokenizer::NextString(Error &error)
 	   line) */
 
 	++input;
-	if (!IsWhitespaceFast(*input)) {
-		error.Set(tokenizer_domain,
-			  "Space expected after closing '\"'");
-		return nullptr;
-	}
+	if (!IsWhitespaceFast(*input))
+		throw std::runtime_error("Space expected after closing '\"'");
 
 	/* finish the string and return it */
 
@@ -190,10 +168,10 @@ Tokenizer::NextString(Error &error)
 }
 
 char *
-Tokenizer::NextParam(Error &error)
+Tokenizer::NextParam()
 {
 	if (*input == '"')
-		return NextString(error);
+		return NextString();
 	else
-		return NextUnquoted(error);
+		return NextUnquoted();
 }

src/util/Tokenizer.hxx

@@ -30,8 +30,6 @@
 #ifndef TOKENIZER_HXX
 #define TOKENIZER_HXX
 
-class Error;
-
 class Tokenizer {
 	char *input;
 
@@ -58,50 +56,42 @@ public:
 	}
 
 	/**
-	 * Reads the next word.
+	 * Reads the next word.  Throws std::runtime_error on error.
 	 *
-	 * @param error if this function returns nullptr and
-	 * **input_p!=0, it provides an #Error object in
-	 * this argument
 	 * @return a pointer to the null-terminated word, or nullptr
-	 * on error or end of line
+	 * on end of line
 	 */
-	char *NextWord(Error &error);
+	char *NextWord();
 
 	/**
-	 * Reads the next unquoted word from the input string.
+	 * Reads the next unquoted word from the input string.  Throws
+	 * std::runtime_error on error.
 	 *
-	 * @param error if this function returns nullptr and **input_p!=0, it
-	 * provides an #Error object in this argument
 	 * @return a pointer to the null-terminated word, or nullptr
-	 * on error or end of line
+	 * on end of line
 	 */
-	char *NextUnquoted(Error &error);
+	char *NextUnquoted();
 
 	/**
-	 * Reads the next quoted string from the input string.  A backslash
-	 * escapes the following character.  This function modifies the input
-	 * string.
+	 * Reads the next quoted string from the input string.  A
+	 * backslash escapes the following character.  This function
+	 * modifies the input string.  Throws std::runtime_error on
+	 * error.
 	 *
-	 * @param error if this function returns nullptr and **input_p!=0, it
-	 * provides an #Error object in this argument
-	 * @return a pointer to the null-terminated string, or nullptr on error
-	 * or end of line
+	 * @return a pointer to the null-terminated string, or nullptr
+	 * end of line
 	 */
-	char *NextString(Error &error);
+	char *NextString();
 
 	/**
 	 * Reads the next unquoted word or quoted string from the
 	 * input.  This is a wrapper for NextUnquoted() and
-	 * NextString().
+	 * NextString().  Throws std::runtime_error on error.
 	 *
-	 * @param error if this function returns nullptr and
-	 * **input_p!=0, it provides an #Error object in
-	 * this argument
 	 * @return a pointer to the null-terminated string, or nullptr
-	 * on error or end of line
+	 * on end of line
 	 */
-	char *NextParam(Error &error);
+	char *NextParam();
 };
 
 #endif